Apparatus having at least two control bars with differing latching arrangements

ABSTRACT

The invention relates to a magnetic tape apparatus having at least two push buttons (31, 32) which, when their push-button bars (33, 34) are pressed in separately, exercise individual functions on apparatus parts, with it being possible for each of the push-button bars (33, 34), loaded in tension by means of springs (50, 51) in the direction of their initial neutral positions, to be arrested in the pressed-in position, and with it being possible for a spring-loaded blocking member (20) which can be moved by all push-button bars (33, 34) and which interacts with latches on the push-button bars (33, 34) to be adjusted in such a way that, when a push-button bar is pressed in, a push-button bar arrested beforehand is released for withdrawal. In addition, the individual latches (52, 53) of at least two push-button bars (33, 34) with the parts of the blocking member (20) which are allocated to the individual latches (52, 53) have latching arrangements of different design. The different latching arrangements are constructed in such a way that the push-button bars (33, 34) having a different latching arrangement, when they are alternately pushed in, are released by the blocking member (20) for withdrawal. Moreover, it is provided that the blocking member (20), when these push-button bars (33, 34) are pushed in together, likewise releases these two push-button bars for withdrawal.

BACKGROUND OF THE INVENTION

The invention relates to a magnetic tape apparatus having at least twopush buttons which, when their push-button bars are pressed inseparately, exert individual functions on apparatus parts. In suchapparatus each of the push-button bars is loaded in tension by means ofsprings in the direction of their initial neutral positions, and isarrested in the pressed-in position. A spring-loaded blocking member canbe moved by all push-button bars, and interacts with latches on thepush-button bars to be adjusted in such a way that, when a push-buttonbar is pressed-in, any push-button bar which was arrested beforehand isreleased for return to the initial position. The individual latches ofat least two push-button bars with blocking member parts allocated tothe individual latches have latching arrangements of different design.

A magnetic tape apparatus of this type is .[.knwon.]. .Iadd.known fromGerman Patent Specification No. 2,233,127 to which U.S. Pat. No.3,900,173 corresponds. In this apparatus, several push-button bars areprovided with latches which engage into recesses of a transverselydisplaceable slide. The latches, after they have displaced the slide bymeans of inclined edges on the recesses during the push-in movement, candrop into allocated latching hollows. The push-button bars thus arrestedin the pushed-in position can therefore set certain operating functionsin the apparatus. When a second push-button bar is pushed in from itsneutral position, this push-button bar also pushes the slide aside viaits latch. If the first push-button bar, which had been arrestedbeforehand, is not secured manually in the pushed-in position, the firstpush-button bar springs out when the second push-button bar is pushedin.

If both push-button bars are pushed in together for another presetfunction, the latches of both push button bars drop behind the latchingedges of the recesses and thus both are locked. It is only possible tounlock these two push-button bars with the aid of a third push-buttonbar having an inclined edge which displaces the slide to the extent thatboth arresting latches are freed from the blocking edges. Allpush-button bars are preloaded in the outward direction by means ofsprings, so that they always return to their initial position when thelatches are released.

With its latch and the associated slide recess, each individualpush-button bar forms a separate latching arrangement. Moreover, the twoindividually lockable push-button bars have latching arrangements of thesame design. In the '173 U.S. Patent there is also a further push-buttonbar with another latching arrangement which is of such a design that itcan disengage the latching arrangements of the two first mentionedpush-button bars in the same way as the non-locking release push-buttonbar.

SUMMARY OF THE INVENTION

In a magnetic tape apparatus, it is the object of the invention tooperate apparatus functions via push-button bars which, even whenpressed in together, can always be unlocked without the use of a specialdisengaging button.

In an apparatus according to the invention the different latchingarrangements are constructed in such a way that the push-button barshaving a different latching arrangement, when they are alternatelypushed in, are released by the blocking member for return to the neutralposition; and that the blocking member, when these push-button bars arepushed in together, likewise releases these two push-button bars forreturn to the neutral position.

This construction has the advantage that, with the push buttons for theindividual functions, when operating the push buttons with only onelatching arrangement or when operating the push buttons with bothlatching arrangements, unlocking is always possible without the aid of adisengaging button specially designed for the disengaging. Thus thedisengaging button is dispensed with. This elimination is important insmall apparatus, such as, for example, car radio-cassette players, inwhich there is little space available on the operating side. Moreover,the number of components is reduced. The manufacturing of an apparatustherefore becomes more economical.

By the use of two types of latching arrangements, it becomes possible,with a push-button bar having one type of latching arrangement, todisengage push-button bars having another type of latching arrangementand vice versa. .[.Itis.]. .Iadd.It is .Iaddend.therefore important thatpush-button bars having two different types of latching arrangements arealways available.

According to a preferred embodiment of the invention, with the blockingmeans for each latch having a blocking edge, running across the push-indirection, and a first sliding edge running at an inclined angle to thepush-in direction, a second inclined sliding edge is provided betweenthe blocking edge and the first inclined sliding edge. The firstinclined sliding edge, when a push-button bar is pushed in, and thesecond inclined sliding edge, during withdrawal, unlock at least oneother push-button bar. Thus the push-button bars, in both directions ofmovement, that is both when entering and withdrawing, can execute anunlocking action. When a push button of one type of latching arrangementis pushed in, the latching arrangement of the other type is disengagedvia the first inclined sliding edge. If push-button bars of bothlatching arrangements are pushed in and if both of these are released,both latching arrangement are disengaged via one of the second inclinedsliding edges.

According to a further embodiment of the invention, it is provided thatthe length of the deflection movement of the blocking member, during thelongitudinal sliding movement of a latch of a latching arrangement alongone of the associated inclined sliding edges, is always greater than thelength of the blocking edge across the push-button bar sliding directionof the other latching arrangement. This ensures that, no matter whethera push-button bar is just pushed in or whether it is released afterpushing in, a latch runs onto an inclined sliding edge and thusdisengages the other latching arrangement or both latching arrangements.Preferably, the first and second sliding edge enclose an obtuse anglewith one another. By the formation of an .[.abtuse.]. .Iadd.obtuse.Iaddend.angle, the frictional forces to be overcome when operating thepush-button bar are kept low.

In this preferred embodiment of the invention, the latches are designedin such a way that the respective push-in displacement of a push-buttonbar is approximately the same up to the unlocking of another push-buttonbar engaged beforehand. The difference in the design of the latches can,for example, consist in their length in the push-in direction or in theattachment of an additional latch. In any case, it can thus be ensuredthat, for unlocking, all push-button bars having different types oflatching arrangements execute the same push-in displacements todisengage. Thus operating is made easier.

In a different embodiment of the invention, with the blocking memberbeing designed as a longitudinally displaceable slide and with a recessin the slide being allocated to each latch, the recesses are formed insuch a way that the slide, as a result of one of the push-button barsbeing pushed in, can be displaced in both directions relative to itsneutral position. By this design of the recesses, it becomes possible tohave both types of latching arrangements work with a longitudinallydisplaceable slide.

Preferably, in the first embodiment of the invention, the blockingmember is designed as a pivotable catch .[.with.]. .Iadd.which.Iaddend.interacts with the latches of all push button bars and can bepivoted by the latches against spring force. A pivotable blocking catchcan be of very compact design, which is of great importance ininstruments of small construction.

It is further desirable that the latches extend tangentially to thecatch pivot axis, and latches of two different latching arrangementshave different tangential extents, with one latch bearing against ablocking edge. Thus more favourable transmission ratios are achieved andthere is no complicated recess formation.

In the first embodiment of the invention, preferably the blocking memberis advantageously made as a plastic injection moulding, with a flexibleplastic arm being integrally provided on it, which plastic arm, when thepush-button bars are pushed in, can be pretensioned in flexible mannerby inclined edges of the push-button bars, which edges run onto theplastic arm. Such a member design can easily be manufactured, and thespring does not require additional assembly.

The invention is described in greater detail with reference to theexemplary embodiments shown in the drawing.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a bottom view of a magnetic tape apparatus, to be fitted intoa car radio, having two push-buttons in their extended neutral position,

FIG. 2 is an enlarged schematic bottom view of a blocking catch andportions of the push-button bars of the apparatus of FIG. 1,

FIG. 3 is a schematic elevation of the construction shown in FIG. 2, and

FIG. 4 is a diagrammatic representation of a latch slide in a secondembodiment, having allocated latches of push-button bars.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The magnetic tape apparatus shown in FIG. 1 has a frame 1, which, via asupport 2, carries a drive motor 3 rotating only in one direction. Thedrive pulley 4 of the motor 3 drives a round belt 5 which is guided overa flywheel 8. The flywheel 8 is journalled in the frame 1 and is firmlyconnected to a capstan shaft 10 and a gear 12. A further gear 14 isrotatably arranged on the flywheel 8 co-axially to the gear 12 via afriction coupling.

Moreover, magnetic tape hubs, which are journalled in the frame 1, arefirmly connected to fast-wind wheels 22 and 23. A play wheel 25 isconnected to one of the magnetic tape hubs via a friction coupling. Amember 26, which is .[.displaceable.]. .Iadd.displaceably.Iaddend.mounted in the frame, supports two gears 28 and 29 next to oneanother. A spring 30 continually presses the member 26 .[.into.]..Iadd.toward .Iaddend.an initial position shown in FIG. 1.

The member 26 bears two pins 28a and 29a which are displaceable in theframe 1 in a triangular hole 28b and a slot 29b respectively.

Two push buttons 31 and 32 are provided for fast forward and reverserunning. These push buttons 31 and 32 are connected to slides 35 and 36via push-button bars 33 and 34. These slides 35 and 36 act on the member26. For this purpose, the slide 35 is provided with an extension 37. Theslide 36 accordingly has a ramp surface 38. The extension 37 and theramp surface 38 act on a pin 39 of the member 26. Moreover, the slides35 and 36 are provided with ramp surfaces 35a and 35b, and 36a and 36brespectively, which can act on pins 74c and 74d respectively of aheadplate (not shown). This headplate lies on the other side of theframe 1.

The gear 29 first comes into engagement with the gear 13 when the button31 is depressed and the extension 37 presses against the pin 39 of themember 26 followed by the pressing in and interlocking of thepush-button bar 33 by a blocking member 20. At the same time, the pin28a executes a movement in the direction of arrow b, and the pin 29aexecutes a movement in the direction of arrow c'. Upon further movement,the pin 29a travels further in the direction of arrow b' and the gear 29comes into engagement with the gear 23. The magnetic tape is now rapidlywound with the magnetic tape hub connected to the gear 23. If, on theother hand, the other push-button bar 34 is pressed in and locked withthe blocking member 20 in a manner to be described below, the run-onsurface 38 acts on the pin 39 of the member 26, as a result of which thepin 28a travels in the direction of arrow c and the pin 29a travels inthe direction of arrow c', as a result of which the gear 29 comes intoengagement with the gear 13, and the gear 28 comes into engagement withthe gear 22. Consequently, the other magnetic tape hub is connected tothe gear 22 .[.is driven.]. for fast winding.

FIGS. 2 and 3 schematically show the interaction of the push-button bars33 and 34 with the blocking member 20, with the slides 35 and 36 shownin FIG. 1 being omitted for the sake of simplicity. The blocking member20 is designed as a catch which can be pivoted about an axis 40. Thecatch 20 consists of a catch body 41 and a flexible plastic arm 42injection-moulded onto this catch body. Because the axis 40 of the catch20 extends perpendicularly to the displacement direction 43 of thepush-button bars 33 and 34, the catch body 41 can pivot in the directionof the double arrow 44. A blocking edge 45 is located in the area of thefree end of the catch body 41. Adjoining the blocking edge 45 is asecond inclined sliding edge 46 which encloses an obtuse angle with afirst inclined sliding edge 47 adjoining it. The free end 42a of theplastic arm 42 can interact with inclined surfaces 48 and 49 of the pushbutton bars 33 and 34.

The push-button bars 33 and 34 are loaded in tension in the outwarddirection by means of spring 50 and 51. The springs 50 and 51 engage onthe frame 1. The push-button bars 33 and 34 are provided with latches 52and 53. The latches 52 and 53 extend tangentially to the catch pivotaxis 40 and have a different length d in the direction toward the catchbody 41. In this embodiment the length of the latch 52 is greater thatthe length of the latch 53.

In FIGS. 2 and 3, the push-button bar 33 is pressed in, so that thelatch 52 is interlocked behind the blocking edge 45. As a result of thepushing in, the inclined surface 48 of the push-button bar 33 pressesagainst the plastic arm 42, and the catch body 41 is thus spring-loadedin the clockwise direction, as a result of which firm locking isobtained. Moreover, it is shown that the push-button bar 34 is alsopressed in at the same time, so that the latch 53 has also moved behindthe second sliding edge 46. The latch 53 has thus not been locked, butis pulled back by the spring 51 in the direction of an arrow 54. Thecatch body 41 thus is pivoted in the counterclockwise direction bymovement of the latch 53 along the inclined edge 46, bending the arm 42and releasing the latch 52. This ensures that, when the two push-buttonbars 33 and 34 are pushed in together, both push-button bars areunlocked when finger pressure on the push buttons is removed at the sametime, and return to the initial neutral position.

In this connection, it is important that latch 52 and the blocking edge45 on the one hand and the latch 53 and the blocking edge 45 on theother hand form different types of latching arrangements. Both latchingarrangements individually make it possible to press in and reliablyinterlock only one of the push-button bars 33 and 34. In this case, thelatching arrangements are constructed such that the push-button barshaving a different latching arrangement will latch individually whenalternately pressed in, by the blocking member 20. However, the sameblocking member 20, when these push-button bars 33 and 34 are pressed intogether, likewise releases these two push button bars for return to theneutral position. In this connection, it is important that the latches52 and 53 extend tangentially to the catch pivot axis 40, and latches oftwo different latching arrangements have different tangential extents,with the distance d (FIG. 2) being smaller than the length of thepossible deflection movement e .[.or g.]. of the catch body 41 which canbe produced by the latch 53.

As is apparent from FIG. 1, an additional extension 55 is provided onthe latch 53. This additional extension ensures that the respectivepush-in displacement of a push-button bar is always approximately thesame up to the unlocking of another push-button bar engaged beforehand.

In a modified embodiment shown in FIG. 4, the blocking member isdesigned as a slide 120. The push buttons 131 and 132 interact withpush-button bars 133 and 134. The push-button bar 133 is provided with alatch 152, and the push-button bar 134 is provided with a latch 153.These latches 152 and 153 engage in recesses 121 and 122 of the slide120. The latches 152 and 153, when the push-button bars 133 and 134 arein the neutral position, lie in front of the front edges 123 and 124 ofthe recesses 121 and 122. Springs 150 and 151 always pull thepush-button bars 133 and 134 into their neutral and initial position atthe edges 123 and 124 so long as they have not been arrested after theyhave been pushed in; while a spring 126 pulls the slide 120 toward theright.

The recesses 121 and 122 are shaped differently and, together with thelatches which can be moved inside them, form different latchingarrangements. Both recesses 121 and 122 are provided with blocking edges145a and 145b which run across the press-in direction of the push-buttonbars 133 and 134 and behind which the latches 152 and 153 can interlock.Second sliding edges 146a and 146b running at an inclined angle to thepush-in direction adjoin the blocking edges 145a and 145b. Firstinclined sliding edges 147a and 147b follow the second inclined slidingedges 146a and 146b in the opposite direction to the push-in direction,and enclose an obtuse angle with the inclined edges 146a and 146brespectively. Of course, it is not absolutely simply facilitate thepush-in movement and therefore the ease of operation. Stop or guidesurfaces 125a and 126b, which run in the push-in direction, are providedbetween the first inclined sliding edges 147a and 147b and the frontedges 123 and 124.

If the push-button bar 133 is pushed in by pressing the push button 131,the latch 152 travels along the guide edge 125a, the first inclinedsliding edge 147a and the second inclined sliding edge 146a so as tothen drop behind the blocking edge 145a. At the same time, the slide 120has moved to the left while the edge 147a is engaged, and then to theright while the edge 146a is engaged, under the biasing force of thespring 126. When the latch 152 passes behind the blocking edge 145a, thespring 126 pulls the slide 120 further to the right until the guidesurface 125b contacts the latch 153. The latch 152 is now in a position,relative to the recess 121, shown as 152'. If the push-button bar 134 isnow pushed in by depressing the push button 132, the latch 153 slidesalong the first inclined surface 147b and pulls the slide 120 to theleft. During this sliding movement of the latch 153 along the firstinclined sliding edge 147b, the latch 152 is released and thepush-button bar 133 returns to its initial position. When thepush-button bar 134 is pushed further, the latch 153 passes along thesecond inclined sliding edge 146b while the slide 120 is pulled to theright, to the blocking edge 145b. Further sliding of the slide 120, dueto the spring 126, then interlocks latch 153 behind this blocking edge.If at this point the push-button bar 133 is pushed in again, the latch152 pushes the slide to the left by its movement along the firstinclined sliding edge 147a, so that the latch 153 is released. Theprecondition for this operation is that the transverse length d of theblocking edge 145b in the recess 122 is smaller than the distance e bywhich the inclined edge 147a in the recess 121 will move the slide 120to the left.

.[.In.]. .Iadd.If .Iaddend.both push-button bars 133 and 134 are pushedin, the slide can be pushed to the left only to the point where furtherslide movement to the right is prevented by contact of an edge 154b inthe recess 122 with the latch 153. The latch 152 is then in the position152c. This means that, when the user stops depressing the two buttons131, 132 the latch 152 is pulled back over the sliding edge 146a bymeans of the spring 150. But this is also adequate to move the slidingedge 146b in front of the latch 153. The spring 151 then pulls out thepush-button bar 134, and the latch 153 travels past the second inclinededge 146b. When both push-button bars 133 and 134 are pushed in andreleased at the same time, both push-button bars will therefore returnfreely into their initial positions.

For perfect functioning of the arrangement according to FIG. 4, it isalso important for the displacement g of the slide 120, when the latch153 slides along the first inclined sliding edge 147b, to be greaterthan the transverse length f of the blocking edge 145a.

In FIG. 4, the latches 152 and 153, in the push-in direction, are shownto be different lengths by the values x and y. These different latchlengths make it possible for the respective push-in displacement of apush-button bar always to be approximately the same up to the unlockingof another push-button bar engaged beforehand.

I claim: .[.
 1. Apparatus comprising:two movable control elementsmovable between respective neutral and operating positions, two latchingmechanisms, each responsive to movement of a respective control elementfrom its neutral to its operating position, for engaging said respectivecontrol element for latching the respective element in its operatingposition, said latching mechanisms being of dissimilar configuration,interlocking means for releasing the latching mechanism associated withone element responsive to movement of the other element to itsrespective operating position, and means, responsive to movement of bothelements from their neutral to their operating positions, for disablingthe latching mechanisms from latching the respective elements, therebypermitting said elements to return to their neutral positions..]. .[. 2.An apparatus as claimed in claim 1, further comprising means for movingan article in a given direction,means for enabling said means for movingresponsive to movement of one of said control elements to its operatingposition, and means for inhibiting said means for moving responsive tomovement of both of said control elements to their respective operatingpositions..].
 3. An apparatus .[.as claimed in claim 2,.]..Iadd.comprising:two movable control elements movable between respectiveneutral and operating positions, two latching mechanism, each responsiveto movement of a respective control element from its neutral to itsoperating position, for engaging said respective control element forlatching the respective element in its operating position, said latchingmechanisms being of dissimilar configuration, interlocking means forreleasing the latching mechanism associated with one element responsiveto movement of the other element to its respective operating position,and means, responsive to movement of both elements from their neutral totheir operating positions for disabling the latching mechanisms fromlatching the respective elements, thereby permitting said elements toreturn to their neutral positions, .Iaddend.characterized in that: saidcontrol elements are push-button bars, movable against a biasing forcein a push-in direction from their respective neutral positions, saidlatching mechanisms include a common spring-loaded blocking memberarranged to be movable in response to movement of at least either ofsaid control elements from its neutral position to its operatingposition, and a respective latch element associated with and movingtogether with each control element, and said blocking member is moved afirst distance .Iadd.in a first direction .Iaddend.transversely to saidpush-in direction.Iadd., and is then moved in a second directionopposite said first direction, .Iaddend.in response to depression of oneonly of said control elements to its operating position, and is moved asecond distance different from said first distance transversely to saidpush-in direction in response to depression of at least the other ofsaid control elements to its operating position.
 4. An apparatus asclaimed in claim 3, in which said blocking member has, for each latchelement, a respective blocking edge extending transversely to saidpush-in direction, and a respective first sliding edge extending at aninclined angle to the push-in direction, characterized in that:saidblocking member has a respective second inclined sliding edge betweeneach blocking edge and the respective first inclined sliding edge,arranged such that upon depression of both control elements, andsimultaneous release of both control elements by a user, engagement ofone latch .Iadd.element .Iaddend.with the respective second sliding edgeunlocks the latching .[.arrangement.]. .Iadd.mechanism .Iaddend.of theother control element.
 5. An apparatus as claimed in claim 4,characterized in that, during sliding movement of a latch .Iadd.element.Iaddend.along at least one of its associated inclined sliding edges,said blocking member moves transversely to said push-in direction adistance greater than a length of the blocking edge, transversely tosaid push-in direction, of the other latching .[.arrangement.]..Iadd.mechanism.Iaddend..
 6. An apparatus as claimed in claim 4,characterized in that said first and second sliding edges of eachrespective .[.latching arrangement.]. .Iadd.blocking member.Iaddend.enclose an obtuse angle with one another.
 7. An apparatus asclaimed in claim 6, characterized in that each of said .[.latches.]..Iadd.latch elements .Iaddend.is designed such that movement of therespective push-button bar is approximately a same distance up to theunlocking of another push-button bar engaged beforehand.
 8. An apparatusas claimed in claim 7, characterized in that said blocking member is adisplaceable slide having a respective recess formed therein in whichthe respective .[.latches.]. .Iadd.latch elements .Iaddend.aremovable,characterized in that said slide is displaced in both directionstransversely to said push-in direction during movement of one of saidpush-button bars from its neutral to its operating position.
 9. Anapparatus .[.as claimed in claim 7,.]. .Iadd.comprising: .Iaddend.twomovable control elements movable between respective neutral andoperating positions, two latching mechanisms, each responsive tomovement of a respective control element from its neutral to itsoperating position, for engaging said respective control element forlatching the respective element in its operating position, said latchingmechanisms being of dissimilar configuration, interlocking means forreleasing the latching mechanisms associated with one element responsiveto movement of the other element to its respective operating position,and means, responsive to movement of both elements from their neutral totheir operating positions, for disabling the latching mechanisms fromlatching the respective elements, thereby permitting said elements toreturn to their neutral positions, characterized in that .Iadd.saidcontrol elements are bars, movable against a biasing force in a firstdirection from their respective neutral positions, said latchingmechanisms include a common spring-loaded blocking member arranged to bemovable in response to movement of at least either of said controlelements from its neutral position to its operating position, and arespective latch element associated with and moving together with eachcontrol element, said blocking member is moved a first distancetransversely to said first direction in response to movement of one onlyof said control elements to its operating position, and is moved asecond distance different from said first distance transversely to saidfirst direction in response to movement of at least the other of saidcontrol elements to its operating position, and, .Iaddend. said blockingmember is a pivotable catch interacting with the .[.latches.]..Iadd.latch elements .Iaddend.of said push-button bars, and saidapparatus includes means for applying a spring force tending to pivotsaid catch in a given direction at least while one of said controlelements is moved from its neutral position, engagement of said catch bysaid .[.latches.]. .Iadd.latch elements .Iaddend.pivoting the catchagainst said spring force.
 10. An apparatus as claimed in claim 9,characterized in that said .[.latches.]. .Iadd.latch elements.Iaddend.extend tangentially to the catch pivot axis, latches of twodifferent latching .[.arrangements.]. .Iadd.mechanisms.Iaddend.extending differing distances in the tangential direction. 11.An apparatus as claimed in claim 10, characterized in that said blockingmember is a plastic injection molding, said means for applyingcomprising a flexible plastic arm formed as part of said blocking memberand arranged for engagement by inclined edges formed on said push-buttonbars. .[.12. Apparatus comprising:two movable control elements movablein a same given direction between respective neutral and operatingpositions, two latching mechanisms, each responsive to movement of arespective control element from its neutral to its operating position,for engaging said respective control element for latching the respectiveelement in its operating position, said latching mechanisms being ofdissimilar configuration, interlocking means for releasing the latchingmechanism associated with one element responsive to movement of theother element to its respective operating position, and means,responsive to movement of both elements from their neutral to theiroperating positions, for disabling the latching mechanisms from latchingthe respective elements, thereby permitting said elements to return totheir neutral positions..].
 13. An apparatus .[.as claimed in claim12.]. .Iadd.comprising:two movable control elements movable in a samegiven direction between respective neutral and operating positions, twolatching mechanisms, each responsive to movement of a respective controlelement from its neutral to its operating position, for engaging saidrespective control element for latching the respective element in itsoperating position, said latching mechanisms being of dissimilarconfiguration, interlocking means for releasing the latching mechanismassociated with one element responsive to movement of the other elementto its respective operating position, and means, responsive to movementof both elements from their neutral to their operating positions, fordisabling the latching mechanisms from latching the respective elements,thereby permitting said elements to return to their neutral positions,.Iaddend.characterized in that said latching mechanisms include a commonspring-loaded blocking member arranged to be movable in response tomovement of at least either of said control elements from its neutralposition to its operating position, and a respective latch elementassociated with and moving together with each control element, and saidblocking member is moved a first distance .Iadd.in a first direction.Iaddend.transversely to said given direction.Iadd., and is then movedin a second direction opposite said first direction, .Iaddend.inresponse to depression of one only .Iadd.of said control elements forunlatching the latch element of the other of said control elements;.Iaddend.and is moved a second distance different from said firstdistance transversely to said given direction in response to depressionof at least the other of said control elements to its operatingposition.
 14. An apparatus as claimed in claim 13, in which saidblocking member has, for each latch element, a respective blocking edgeextending transversely to said given direction, and a respective firstsliding edge extending at an inclined angle to the given direction,characterized in that:said blocking member has a respective secondinclined sliding edge between each blocking edge and the respectivefirst inclined sliding edge, arranged such that upon depression of bothcontrol elements, and simultaneous release of both control elements by auser, engagement of one latch .Iadd.element .Iaddend.with the respectivesecond sliding edge unlocks the latching .[.arrangement.]..Iadd.mechanism .Iaddend.of the other control element.
 15. An apparatusas claimed in claim 14, characterized in that said blocking member is apivotable catch interacting with the latches of said push-button bars,and said apparatus includes means for applying a spring force tending topivot said catch in a given direction at least while one of said controlelements is moved from its neutral position, engagement of said catch bysaid .[.latches.]. .Iadd.latch mechanism .Iaddend.pivoting the catchagainst said spring force.
 16. An apparatus as claimed in claim 15,characterized in that said .[.latches.]. .Iadd.latch elements.Iaddend.extend tangentially to the catch pivot axis, .[.latches.]..Iadd.latch elements .Iaddend.of two different latching arrangementsextending differing distances in the tangential direction.
 17. Anapparatus as claimed in claim 16, characterized in that said blockingmember is a plastic injection molding, said means for applyingcomprising a flexible plastic arm formed as part of said blocking memberand arranged for engagement by inclined edges formed on said push-buttonbars. .[.18. Magnetic tape apparatus having at least two push-buttonswhich, when their push-button bars are pressed in separately, exerciseindividual functions on apparatus parts, with it being possible for eachof the push-button bars, loaded in tension by means of springs in thedirection of their initial neutral positions, to be arrested in thepressed-in position, and with it being possible for a spring-loadedblocking member which can be moved by all push-button bars and whichinteracts with latches on the push-button bars to be adjusted in such away that, when a push-button bar is pressed in, a push-button bararrested beforehand is released for withdrawal, the individual latchesof at least two push-button bars with blocking member parts allocated tothe individual latches, having latching arrangements of differentdesign, characterized in that the push-button bars (33, 34; 133, 134)having a different latching arrangement, when they are alternatelypushed in, are released by the blocking member (20, 120) for withdrawal,and that the blocking member (20, 120), when these push-button bars (33,34; 133, 134) are pushed in together, likewise releases these twopush-button bars for withdrawal..]. .[.19. Magnetic tape apparatusaccording to claim 18, with the blocking member for each latch having ablocking edge running across the push-in direction, and a first slidingedge running at an inclined angle to the push-in direction,characterized in that a second inclined sliding edge (47; 147a; 147b) isprovided between the blocking edge (45; 145a, 145b) and the firstinclined sliding edge, with the first inclined sliding edge (47; 147a;147b), when a push-button bar (33; 133; 34; 134) is pushed in, and thesecond inclined sliding edge (46; 146a; 146b), during withdrawal,unlocking at least one other push-button bar (34; 134; 33; 133)..]..[.20. Magnetic tape apparatus according to claim 19, characterized inthat the length (e.g) of the deflection movement of the blocking member(20, 120), during the longitudinal sliding movement of a latch (52;152a, 152b) of a latching arrangement along one of the associatedinclined sliding edges (46, 146a and b; 47, 147a and b), is alwaysgreater than the length (d; f) of the blocking edge (45, 145a and b)across the push-button bar sliding direction of the other latchingarrangement..].